/**
 * Module dependencies.
 */
import './polyfills'
import fs from 'fs'
import Debug from 'debug'
import http from 'http'

import app from './app'
import { utils } from './common'

const debug = Debug('app:server')


/**
 * Get port from environment and store in Express.
 */

const port = normalizePort(process.env.PORT || '8000');
app.set('port', port);

// 读取前端编译生成的文件列表记录
if (utils.isProd(app)) {
  const content = fs.readFileSync(utils.getAssetFile('manifest.json'), 'utf8')
  app.set('assetsManifest', JSON.parse(content))
}

/**
 * Create HTTP server.
 */

const server = http.createServer(app)

/**
 * Listen on provided port, on all network interfaces.
 */

server.listen(port);
server.on('error', onError);
server.on('listening', onListening);

/**
 * Normalize a port into a number, string, or false.
 */

function normalizePort(val) {
  const port = parseInt(val, 10)

  if (isNaN(port)) {
    // named pipe
    return val;
  }

  if (port >= 0) {
    // port number
    return port;
  }

  return false;
}

/**
 * Event listener for HTTP server "error" event.
 */

function onError(error) {
  if (error.syscall !== 'listen') {
    throw error;
  }

  const bind = typeof port === 'string' ? 'Pipe ' + port : 'Port ' + port

  // handle specific listen errors with friendly messages
  switch (error.code) {
    case 'EACCES':
      console.error(bind + ' requires elevated privileges');
      process.exit(1);
      break;
    case 'EADDRINUSE':
      console.error(bind + ' is already in use');
      process.exit(1);
      break;
    default:
      throw error;
  }
}

/**
 * Event listener for HTTP server "listening" event.
 */

function onListening() {
  const addr = server.address()
  console.log(`Start server at http://127.0.0.1:${addr.port}`)
}
